Does the Panasonic EverVolt battery meet the same standards as Panasonic's highly-rated solar panels? Having debuted in 2019, the Panasonic EverVolt battery was introduced as a new solar energy storage option for both residential homes and small-scale commercial properties.

EverVolt batteries can be paired with already existing solar systems, either Panasonic or another brand, and were recently redesigned to be smaller so that you can install more batteries in a smaller space. 

Solar and energy storage solutions are becoming an increasingly popular form of renewable energy for homeowners. If home solar and energy resilience interest you, pairing the EverVolt panels with the Panasonic EverVolt home battery is a great choice. 

What EverVolt battery models are available?

The Panasonic EverVolt's DC and AC-coupled batteries look very similar from the outside. Image source: Panasonic 

The EverVolt battery is Panasonic’s first residential solar battery storage option. The EverVolt utilizes NMC chemistry, which we will detail below, and is available in two models: 

• The AC-coupled model with a built-in inverter
• The DC-coupled model that does not include an inverter

As a general rule of thumb, AC batteries are best for connecting to existing solar panel systems, while DC batteries are better suited for new solar panel installations. 

You can read more about the pros, and cons, and differences between AC and DC batteries here. 

Along with different models, the EverVolt also has two different versions: the Standard and the Plus. They have slightly different specifications, and deciding which one is better for you depends on your energy needs. 

Key things to know about Panasonic EverVolt batteries

First, it is important to note that the EverVolt batteries are modular, meaning they come in battery packs and they are easy to add onto if you need more storage in the future. Both the AC and DC batteries offer storage options starting at 11kWh, but you can combine up to 6 Plus battery models for a total of 102 kWh worth of storage.

Battery specifications can get a little confusing, so we will start with a table to break them down.  

Note: Information about the EverVolt's depth of discharge is unavailable at this time.

Usable capacity 

The usable capacity is the amount of stored energy within your battery that your home can use, in this case it is 11.4 kWh for the Standard versions and 17.1 kWh for the Plus models. 

What that means in most real-world scenarios is that the Standard battery will provide about 6 hours of backup energy while the Plus is estimated to provide 9 hours of backup power.  

Continuous power rating 

This is the amount of energy that your battery can put out at once, which is important because this determines if your battery can provide power to appliances that need continuous power, like a refrigerator.

A continuous power rating of about 5 kW can be expected in most batteries, the Standard version falls a bit short on this at 4.6 kW but not by much.

Round trip efficiency 

Round trip efficiency is an important factor to take note of - it is the level of energy that is put into a battery storage system versus the amount of energy needed to store it. 

For instance, the DC-coupled battery has a round trip efficiency of 90%. This means that for every 10 kWh of energy that is put into the DC-coupled system, you will be able to get a power output of about 9 kWh from the stored energy. 

The loss of energy occurs when it is transferred from the solar panels to the battery and then to your home. However, there is less energy loss when you use a DC-coupled battery (as shown by its higher round trip efficiency).

Chemistry 

The Panasonic EverVolt’s chemistry is a nickel manganese cobalt (NMC) lithium ion battery. NMC batteries can hold a lot of energy in a small amount of space, making them more practical than older lead-acid battery models. NMC batteries also have a lifespan of up to 10 years. 

How much do EverVolt batteries cost?

You can anticipate spending around $15,000 to $20,000 for an EverVolt battery, including the installation.

Keep in mind, this is just an estimate. Battery costs can be hard to pinpoint because they depend on local installation costs, the complexity of your installation, and which model and version of the EverVolt you choose.  

There are various state, utility, and federal incentives that can reduce the cost of an energy storage system. 

What is EverVolt’s warranty?

Panasonic does offer a competitive 10-year limited warranty for their batteries, which covers both product workmanship and performance. The workmanship warranty will cover any workmanship defects to the product prior to 10 years or an energy output of 7.56 MWh (or a little over 7,000 kWh) - whichever comes first. Make sure to register your battery within 60 days of the installation to qualify for the warranty. 

The performance warranty is also 10 years; it guarantees that the battery will retain at least 60% of its nominal energy, or the initial rated energy capacity, as long as the system has operated under normal use. 

Recharging batteries reduces their capacity to store the same amount of energy over time, so some reduction in performance is expected. But if after 10 years your battery stores less than 60% of its initial capacity, the warranty will be put into place.

Is the EverVolt battery worth buying?

What the Panasonic EverVolt lacks in its throughput and continuous power rating, it makes up for with an excellent round trip efficiency, usable capacity, and trusted brand name. So yes, we believe that the EverVolt is worth the cost.

One thing that the Panasonic battery offers that many other batteries don’t is its ability to connect to a non-solar generator in the event of days-long grid outages. That means that your battery can be charged with a gas-powered generator during true emergency situations. 

You can even install a Panasonic EverVolt if you do not have a solar system, it can be charged from the grid to store surplus energy ready for backup power when the grid fails. 

If you decide a Panasonic EverVolt system is right for you, the best way to get one installed in your house is to work with a pre-approved Panasonic installer. A pre-approved installer will be covered under the warranty and will be able to answer all of your battery-related questions.